Granulating apparatus



Nov. 3, 1936. J. c. KOPF 2,059,249

GRANULATING APPARATUS 7 Sheets-Sheet 2 Filed March 10, 1934 8 INVENTOR fO/l/V 6. AaPF ATTORNEY Nov. 3, 1936. J. c. KOPF 2,059,249

GRANULATING APPARATUS Filed March 10, 1954 7 Sheets-Sheet 3 INVENTOR Ja'Ar/vf/fopp BY ATTORNEY J. c. KQPF GRANULATING APPARATUS Nov. .3, 1936.

7 Sheets-Sheet 5 Filed March 10, 1934 INVENTOR Joy/v 6. fla BY ATTORNEY.

Nov. 3, 1936. K PF' 2,059,249

GRANULAI'ING APPARATUS I Filed March 10, 1934 7 Sheets-Sheet s war/ 112)?! INVENTOR Jo/7W6? fiopF :ATI'ORNEY Nov. 3, 1936. J. c. KOPF 2,059,249

GRANULATING APPARATUS v Filed March 10, 1934 7 Sheets-Sheet '7 INVE'NTOR Y Jo'hw 6. K02

ATTO R N EY Patented Nov. 3, 1936 -The coffee fruit, generally, consists of. two parts, each containing a single seed or bean. These beans are flattened laterally and fit together, except in certain instances.

The coffee bean withivhich the consumer familiar, is only a small part of the fruit. The fruit, which is the size of a small cherry; has, "like the cherry, an outer fleshy. portion called the perlcarp. Beneath this is apart like tissue paper, spoken of technically as the parchment, but known scientifically as endocarp.- Next in position to this, and covering the entire seed or spermoderm", which means the seed skin, and is referred to in the trade as the silver skin. This skin or covering, surrounds the entire bean and extends into the cleft thereof.

The processes for preparing the green coffee for roasting need not here be described. When the coffee is ready for roasting, the pericarp, the e'ndocarp. and the. spermoderm have been removed excepting that portion of the spermoderm which extends into the cleft of the bean; and this portion cannot. be removed as it is tightly embedded in the foldbf the cleft. After the coffee is roasted the spermoderm embedded in the cleft has become a very light, flaky, highly fragile material; Inthis form it is known in the trade Roasted cofiee must be broken up into fairly small pieces to release all of the imprisoned chaflf which is in is the so-called fairly large light I recognized among coffeeexperts and analysts'that there aretwo difierent methods of determining the different qualities of coffee. One of "these is by analytical methods which have been developed in the chemical laboratory, the, other by the so-called organoleptic tests based on sensory reactions; the appearance, the odor or aroma, and the taste or flavor. For coffee, analytical tests alone are insufficient and are, relied on for the determination of certain ingredients and for extractive data, and quality, as used in itsgenerally accepted sense, can be ascertained only by theapplication of sensory tests either before or after it has been subjected to some form of treatment to bring 'it into the condition in which it is'ordinarily employed.

The appearance of the coffee after it has been granulated and prepared for beverage purposes should be clean cut and uni r n colorand-in UNITED STATES PATENT OFFlCE Burns & Sons, Inc., New York, N. Y., a mo! ration of New York;

Application March 10, 1934, SerlalNo. 714,929

- 10 Claims. (01. 83-18) This invention relates to machine and method for granulating roasted cofiee and preparing it as a suitable product for producing a satisfactory distribution of the various sizes of granules. The beverage must be'clear andof the desired color and the flavor and the aroma must conform to certain arbitrary standards. 'Flavor and aroma -fusion of chair has a. disagreeable acrld flavor.

Small quantities of chafl in well made beverage coflee contribute a not unpleasant bitterness which blends well with the other ingredients composing the elusive-and easily ruined flavor. 20' Q It adds a piquancy and 'acts condimentally, while large amounts overbalance the finer flavoring principles or ethereal compounds and quickly depreciate, the flavoring value. Because of the lmequal distribution of chaif throughout the 25 mass of granulated coffee, and for the'purpose of improving the appearance of the finished coffee, it has been the custom in the trade to remove the chaff from the coifee and throw it away. This resulted not only in the production of a coffee 30 of somewhat inferior beverage properties, but also resulted in a decided loss, aschaft constitutes from 1% to 2% in the weight of coifee depending upon where the coffee is grown.

' Roasted cofiee is a very brittle substance and "if roughly handled readily breaks into small pieces. To secure the best results in any of the difierent methods eof brewing coffee such as the pot, percolator or drip method, it is necessary that the ground coffee contain a definte propor- 40 tion of various size granules for each particular method. The proper proportions of difierent size of granules in'coifee are determined by various methods which need not here be described.

methods, the chair aids by forming a mat or 56 filtration pad.

It can therefore be readily seen that to produce a beverage of uniform quality, flavor, and aroma from any coflfee, it is essential that the proper percentages of different sizes of granules are present and also that the percentage of chaff throughout the entire batch of prepared coffee be uniform.

It is well known in the trade that if granulated coffee and chaff be gently rubbed between the .palms of the hands, the chaif will be cut up by "which are almost as fine as dust. In this condi-' tion it is readily blended with the granular coffee and has no tendency to lie in streaks or become stratified. Therefore, it follows that a beverage brewed from coffee prepared inthis manner will be uniform in quality, strength and aroma throughout the entire batch of coffee.

When granulated coffee is beaten or violently agitated in an endeavor to cut up or break up the chaff, the edges of the ground coffee are broken or chipped ofl, producing a high percentage of coifeedust or fine. When coifeeis brewed by the pot or boiling method from granulated coffee containing a high percentage of fine, it results in a beverage having a muddy appearance and inferior in flavor because'of the large quantity of fine insoluble solids held in suspension. In the case of coffee brewed by percolating or drip methods, the excessive fine forms a mat of such density as to retard the fiow of water, at or near the boiling point, through the mass of prepared coifee so ,that not only the oils and fats are extracted from the granulated coffee but also the other constituents which detract from the fiavor and aroma of the beverage.

If in addition to being violently agitated the mixture of granulated coflee and chaff is sub- Jectedto a pressure, the product has a fuzzyappearance; and the pressure releases volatile, essential oils of coffee which results in more rapid deterioration of ion granulated coffee.

I have discovered that if streams of comminuted coffee containing chair, moving in opposite directions, or in the same direction at different velocities, be made to intersect or act upon each other, the result is the same as produced by gently rubbing'coifee and chaff between the palm of the hands. The chair is cut up by the action of the sharp edges of the granulated coffee and coated with the exposed oil. The

resultant product is substantially homogeneous, willcontain a uniform proportion of the various sizes of granules, and will also contain the same percentages of chaff as is found in the original ung'round bean.

I have also discovered that if roasted coflee is cracked in particles sufiiciently small to liberate all of the imprisoned chaff, that if this liberated chaff is acted upon by the relatively coarse pieces of coffee, the resultant finished product has a better, more clean-cut appearance, and has decided advantages from the point of view of eye appeal.

The object of the present invention; is to pro- 1 vide a machine wherein the roasted coffee beans are broken or cracked, wherein the cracked cofle} 6 and I, as shown in Figs. 1, 2 and 4.

is made to act upon the liberated chaff, wherein the cracked coflee is then granulated to a desired fineness, and wherein comparatively thin streams of granulated coffee containing chair are made to move to cause the granulated coffee and the chaff to act upon each other by their relative contacting movement, all in a single operation.

A further object is to provide a machine which may be rapidly and accurately set for any fineness or granulation and which will consistently produce and reproduce such granulations.

Another object is to provide a machine wherein small batches of roasted coifee may be granulated and preparedand which shall completely clean out at the end of each operation or batch.

These and othenobjects and advantages of the invention will be described in connection with the accompanying drawings, inwhich:

Fig. 1 is a vertical section through the machine;

Figfi2 is a horizontal section on line 2-2 of Fig. 1, showing one of the granulating elements and coffee treating mechanism;

Fig. 3 is a vertical section of a modification of the rotatable granulating element;

.Fig. 4 is a horizontal section on line 4-4 of Fig. 1, showing the fixedgranulating element which cooperates with that shown in Fig. 2;

Fig. 5 is a perspective view showing the construction of one form of coffee treating elements:

Fig. 6 is a longitudinal section on line 6-6 of Fig. 7 showing -a machine having a horizontal motor and vertical granulating elements; I

Fig. 7 is a vertical section on line 1-1 of Fig. 6;

Fig.- 8 is a perspective view of one of the coffee treating elements shown in Figs. 6 and 7;

. Fig. 9 is a. horizontal section'similar to Fig. 2'

ut having a modified form of coffee'treating mechanism;

Fig. '10 is a fragmentary vertical section through a the coffee treating mechanism of Fig. 9; a

'struction of the cofiee treating element of Fig.

13; and I Fig. 15 shows a modification in which the coffee is finish ground, before the chaff is reduced.

The machine shown in Figs. 1 to 5 and Fig. 12

has a casing or frame I containing cooperating granulating elements 2 and 3 which in this instance are in the form of plates mounted horizontally within the frame. These plates are secured to carriers. 4 and 5 respectively, by screws Granulating plate 2 is rotated by motor 8 having its shaft 9 secured to plate carrier 4 by key II and set screw ll, rotation being in the direction of the arrow in Fig. 2. The motor may 'be ventilated by providing suitable openings I 2 leading into the side of the frame I as shown in Fig. 1. Granulating plate 3 is stationary but adjustable toward and away from plate 4 to vary the fineness of the grind and to compensate for plate wear.

To provide such adjustment, the hollow shank ofplate carrier 5 is externally threaded at II to sleeve I I which is rotatably mounted in a support-Jinn the top of the frame I. Sleeve ll carries an upper collar l8, which is secured thereto by set screw l1, and a nut' l3 which is secured to the top of the sleeve by set screw I9. Collar It carries a control member such as a lever 20 extending beyond the frame Movement of this lever to the right or left, as viewed in Fig. 12, rotates sleeve I4 and causes plate 3 to move toward or away from plate 2, cooperating lugs 2| on plate carrier 5 and support |5 preventing said plate carrier from rotating. The adjustment of this mechanism to provide a plurality of different grinds, and to compensate .for plate wear, will hereinafter be described. 1

Support IS with the .entire plate adjusting.

mechanism is secured to the frame -I by suitable screws 22 as shown in Figs. 1 and 12. By removing the screws 22 the support l5 together with all of the plate adjusting mechanism may be removed from the machine. A hopper 23 is mounted inany suitable manner, its snout extending intothehollow shank of plate carrier 5 for feeding the coffee beans to the granulating element.

Granulating plates 2 and 3' are provided with feeding or conveying and breaker flights 24 and 25 respectively, and with a plurality of cooperating circular sets of teeth 26,21 and 29, 29 as shown in Figs. 1 to 4. These sets of teeth are arranged in concentric circles, the inner sets 26 and 21 comprising relatively widely spaced teeth for cracking the coffee, and the outer sets 28 and 29 comprising relatively closely spaced teeth for finishing the granulation.

The respective inner and outer concentric sets of teeth are separated by a dished annular space 32. Coffee, in the bean, coming from the hopper 23 through its spout, is first engaged by the feeder and breaker flights 24, 25 where the coffee beans are broken up into large pieces and conveyed into the bite of the cracker teeth 26, 21. Here the broken up coffee is reduced to entirely liberate the imprisoned chaff. From the cracker teeth the cracked coffee and chaff pass into the annular .space 3|). There being no conveyor flights in this space, the cracked coffee and chaff fill the space and are then acted upon by coffee and chaff coming from the. cracker teeth. This action cuts up the chaff and causes the cracked coffee and chaff to flow into the bite of the finisher teeth 28,29.

This invention is not limited to two sets of 'teeth, as for some classes of work the use of three or even more spaced sets of concentric rows of, teeth may be desirable to obtain the desired gradual reduction of size of coffee granules.

Occasionally stones, nails, and other foreign hard objects enter the machine through the hopper 23 together with the cofiee. To prevent injury to the plates or granulating elements-by such foreign hard objects, modified grinding ele-' ments such as are illustrated in Fig. 3 may be adopted. In this figure, the lower granulatlng element is made in two sections comprising an inner disk 3| containing the flights 24 and an outer annular section 32 containing teeth 26 and 28. Section 32 is secured to plate carrier 4'by screws 33 and the inner edge of such section overlaps the peripheral edge of .disk 3|, thereby forming a frictional joint 34 with the disk which is not otherwise secured to .the plate car'- rier. If a hard foreign object becomes wedged between flights 24-25 the wedg'ing action will stop the rotation of disk 3| and interrupt the flow of goods to the cracker teeth. -The operator,

noting the interruption, may stop'the machine,

- discharge opening 36 leading to a spoutf31 and has spaced annular barriers. 38 and 39 which extend inwardly from opposite sides of the chamber between-the granulating plates and the discharge opening 33 as shown in 'Figs. 1 and 2. Hence, the granulated goods thrown outwardly by the granulating platesmust pass under barrier 38 and over barrier 39 before being discharged through opening 36 and spout 31. accomplish this, one or more arms or fliers 40 are provided, which are secured to the rotatable plate carrier 4, two such arms being shown for purpose of illustration in Figs. 1 and 2. These arms, which are alike, are flat and straight at 4|, have a plough-shaped extension 42 between barriers 38 and 39 and a flat pusher extension 43 outwardly of barrier 39, the construction of the arms being clearly shown in Fig. 5. The pusher 43 may have an-ape'iture 44.

The size of the finishedgranulated coffee produced by the machine depends upon the spacing of granulating plates 2 and 3. When adjusting the plates in the first instance, or at any time to is rotated until plates 2 and 3 just click,.lever 20 still being held in contact with pin 45. Nut I8 is then backed up to just clear the plates. With the parts in this position, set screw i1 is tightened to sleeve l4. Thereafter, movement of lever 2|] to the left, as viewed in Fig. 12, causes separation of the granulating plates. Suitable graduations 46 as shown in Fig. 12 may be provided to indicate predetermined sizes of granulated coffee. I

Granulating elements 2 and 3 having beenadjusted to produce the desired fineness of finished goods, the operation of the machine is as follows: Coffee in the bean, passes from hopper 23 through the hollow shank of the fixed plate carrier it into the bite of the breaker and conveyor flights 24 and 2.5, through the cracker teeth 26, 21, annular space 30, finisher teeth 28, 29, whence it is discharged into that part of the annular chamber 35 lying within the depending barrier 33. The granulated coffee and chafl? fall to the bottom 41 of the annular chamber 35 where it is engaged by the flat portions-4| of the arms or fliers 40. This fiat portion 4| sets up a motion in a thin stream of coffee corresponding tothe thickness of such flat portion; such motion being rotary due-to the rotation of the arms 40 and also outward along the leading edge of the fiat portion 4|. This thin layer of coflee. in its combined rotary and straight-line motion acts upon of the barrier 38 and the bottom 41 of the an:

nular chamber 35 can pass through this narrow opening into the space between the barrier 38 and the barrier 39. Coffee passing under the barrier 39 after having been treated in chamber 35 for further reduction of ,chafl continues toremove cover support I5 and ,the associated ad-- Cir move along the leading edge of the arms 40 until it impinges on the inner face of the barrier 38 whereupon it is plowed upward and outwardly by the plow-shaped members 42 of the arms 40 to form streams which further reduce the chaff by the relatively different speeds of the contact-v ing ground material. After the coffee has been plowed over the barrier 39 it falls into a.circular channel or furrow 48 where it is given a circular motion by the pusher 43, some of the coffee being rotated in the furrow, some of it passing out through the opening 36 and some of it passing through the aperture-44 in the pusher. tion being continuous as long as coffee is passing through the plates, successive ridges of coffee, at low velocity, are laid upon the stream of coffee being rapidly rotated in the furrow 48. This continuous action of relatively thin streams of coffee intersecting and acting upon each other by portions moving at relatively different speeds cause the chaff to become further reduced and coated with the oil of coffee and either adhere to the larger granules of coffee or become entirely coated with the very fine granules of coffee and at the same time causes the entire coffee to become thoroughly mixed so that the finished product as discharged from the spout 31 will at all times contain a uniform percentage of the various sized granules as well as of chaff. Owing to the discharge opening 36 being restricted as shown in the drawings, a mass or bulk of the treated material is caused to accumulate in chamber or furrow 48 for securing the above further action and treatment.

Figs. 6 to 8 show a modification of the invention, in which motor 8 is mounted horizontally and granulating elements 2 and 3 are mounted vertically within a cylindrical casing 49. Granulating element 2 is rotated by motor 8 as previously described, while stationary plate 3 is screwed or otherwise secured to the head 50 which has an inlet passage for connection to the feed hopper. Coffee treating chamber 52 has an annular barrier 53 which extends inwardly between the granulating elements and tangential discharge opening 54 which is formed adjacent to and 58 which lie on opposite sides of the barrier 53 and are connected by U-link 59 which straddles'the barrier. It also has a paddle-like extension 60 which rotates adjacent to the peripheral edge of the granulating elements and sweeps the granulated goods toward the plough 51. Said plough 51 is curved more abruptly than plough 58 in order to throw the goods beyond barrier 53 while plough 58 is flatter to avoid returning 4 the bulk of the goods across the barrier. Flier 56 has a single plough shaped extension 6| which is on the same side of the barrier as plough 51 and is curved like plough5'l. It also has a paddle-like extension 62 which lies on the opposite or discharge side of barrier 53 and is connected to plough 6| by a U-shaped link 63 which straddles the barrier, paddle 62 being in reasonably close running contact with the barrier and the adjacent wall of casing 49 so as to move the finished goods through discharge opening 64. As

in the machine previously described, partial re-' duction of the chaff is accomplished by the rub- The acules before the product is discharged by paddle 62 through discharge opening 64.

Figs. 9 to 11 show a modified chaff reducing and coffee treating mechanism which differs from that shown in Figs. 1, 2 and 4 in that annular chamber 35 has only one barrier 38, (barrier 39 being omitted) and that the fliers are of modified construction. In this form of the invention it is simply necessary to carry the goods under barrier 38 into the region of peripheral discharge opening 36. To accomplish this fliers 65 are provided having plough shaped extensions 66, vertical baffles 61, and pushers 68. Pushers 68 are provided with apertures 69. The fliers are also provided with a flat portion 10.

In this type of coffee treating mechanism, coffee in the bean passes from hopper- 23 through the hollow shank-of the fixed plate carrier 5 into the bite of the breaker and conveyor flights 24 and 25, through the cracker teeth 26, 21, annular space, finisher teeth 28, 29, whence it is discharged into that part of the annular chamber 35 lying within the depending barrier 38. The granulated coffee and chaff fall to the bottom 41 of the annular chamber 35 where it is engaged by the fiat portion of the arms or fliers 65. This flat portion 10 sets up a motion in a thin stream of coffee corresponding to the thickness of such fiat portion, this motion being rotary due to the rotation of the arms 65 and also outward along the leading edge of the flat portion 10. The coffee moving along the fiat portion 10 is carried outward until it strikes the leading edge of the baffles 61, whereupon it is scooped up by the plough shaped extension 66 and laid down in a ridge over the top of the trailing edgeof the barrier 61.

The ridge of granulated coffee which has been ploughed over the trailing edge of the baffles 61 will lie in the path of the pusher 68. The pusher 68 will impart a rotary motion to this granulated coffee; some of the coffee will pass through the discharge opening 38, some of it will pass through the apertures 69, while other portions thereof will be pushed back inwardly' and will be again subjected to the ploughing action of the extension 66.

Figs. 13 and 14 show another embodiment of the coffee treating mechanism wherein both barriers are omitted from the annular chamber 35.

In this form of the invention fliers H are em ployed having plough shaped extensions 12 and I3 separated in front by vertical baffles 14 and having flat paddles which rotate adjacent the periphery of chamber 35. As the fliers rotate through the. granulated coffee and chaff a thin layer of such product moves outwardly as previously described until it meets baflle I4 whereupon it is lifted by the plough shaped extension 12 over such baffle 14 and into the path of the plough shaped extension 13. The plough shaped extens ion I3 is somewhat flatter than the plough sha'ped extension "and therefore ploughs back into the path of the plough shaped extension 12- only a portion of the product in its path. The balance of the product spills outwardly of the .ploug h shaped extension 13 and into the path of the paddle or pusher l whereupon it is subjected to a rotary motion, some of it passing out two members 12 and I3 intersect each other in relatively opposite directions and that that portion which spills outwardly from the extension l0 It acts upon and is acted upon by the stream of cofiee being rotated by the pusher 15.

Fig. 15 shows a modification in which the granulating elements it and H are provided with but single rows of teeth '18- and it. In this form,

1 the roasted coffee beans pass from the hopper 23 through the hollow shank of the fixed plate carrier 5 into the bite of the breaker and conveyor flights 24 and 25 thence into the bite of the teeth l6 and Ti. Broken coffee is gradually reduced to a predetermined fineness and passes into the annular chamber 35 where it is treated as'previously described to produce a finished homo: geneous product containing practically indiscernible chair. 4 Having -thus described my invention, what I claim as new, novel and useful, is:

1. In a machine for granulating and treating coffee, in combination with cooperating grinding plates, means for feeding material between said 9 plates, an annular chamber having a restricted peripheral discharge opening for. receiving and discharging material thrown outwardly by said a plates, a plurality of spaced annular barriers in said chamber extending from opposite sides thereof between said plates and said discharge opening, a rotatable arm in said chamber carrying an extension between the outer barrier and the outer wall of said annular chamber and adapted to move granulated coffee around the 40 annular chamber formed by said barrier and said barrier wall and discharge a portion thereofthrough the discharge opening, a plough-shaped extension carried by said arm between said barriers and adapted to throw said granulated coffee over theouter barrier and lay it in a ridge on the granular cofiee being rotated by the outer extension.

2. In a machine for granulating and treating coflee, in combination with cooperating grinding plates, means for feeding material between said 5 plates, an annular chamber having a restricted discharging granulated coffee thrown outwardly by said plates; an annular barrier in said chamber between said plates and said discharge opening,-

a rotatable arm in said chamber, a plough shaped extension carried bys'aid arm inwardly of said barrier to lift said granulated coflfee over said barrier, and an extension carried by wardly of said barrier to move said material through said discharge opening.- I

3. In a machine for granulating and treating zcofiee, in combination with a rotatable grinding plate, a stationary grinding plate, means for adjusting said stationary plate toward andaway from said rotatablaplate tovary the fineness of.

the grind, means for feeding coffee between said plates, an annular chamber around said plates adapted to receiveand accumulate a bulk of the ground material from said plates, and an arm in said chamber movable with said rotatable plate to rotate in saidbulk of material, said arm having a cross section substantially lessthan said chamber whereby movement-is imparted to er- -;tions 61 said bulk of material diflereniffrom that peripheral dischargeopening,for,receiving and said arm outgrind, means for feeding material between saidplates, an annular chamber around said plates adapted to receive and accumulate a bulk of the ground material from said plates, and an arm associated with at least one of said plates to rotate in said bulk of material, said arm having a cross section substantially less than said chamber said bulk of material different from that of other contacting portions of said material for causing the cofiee granules to act upon and further r e duce the chad, a restricted discharge opening for said chamber, means to prevent direct radial discharge of material from said chamber through said opening, and means rotatablewith said am to discharge portions of the bulk, after treatment by said arm, through said discharge opening.

5. In a machine for granulating-and treating coffee, in combination with cooperating grinding plates means for feeding bean coflee between said plates, an annular chamber around said plates adapted to receive and accumulate a bulk of the ground material from said plates, and a rotatable element in said chamber, said element being whereby movement is imparted to portions of adapted to engage portions only of'said bull: of

material for imparting movements to said portions of said bulk of material different from that of other contacting portions of the material for causing the cofiee granules to act upon and further reduce the chaff, a restricted discharge opening for said chamber, means to prevent direct radial discharge of material from said chamber through said opening, and means rotatablewith said element to discharge portions of the bulk,

after treatment by said element through said discharge opening.- L,

' 6am a machine for granulating and treating cofi'ee, a pair or cooperating grinding elements, means for rotating at least one of said elements, an annular chamber adapted to receive and 'accumulate a bulk of the ground material from said elements, and an. arm connected with the rotating element and extending into said chamber, said arm having a cross section substantially less than that of said; chamber whereby movement is imparted to portions of saidbulk of ma terial different from that of other contacting portions of said material for causing the coffee gran,-

ules to act upon and further reduce the chart, a

Q portions of the bulk, after treatment by said arm,

through said discharge epeningg 7; In a 'machinefor granulating and treating cofiee, incombination with cooperating-grinding plates, means for feeding material between said plates, an annular chamber having a restricted peripheral discharge opening for receiving and discharging granulated coffee thrown outwardly l by said plates, an annular barrier in said'cham-- and means rotatable with said arm to discharge ber between said plates and said discharge opening, means rotatable in said chamber to engage a portion of the material accumulated therein for parting movement to a portion oisaid materiai diii'erent from that of the remainder thereof so as to cause the coffee granules to act upon and further reduce the chair, and means to impel the material thus treated over said barrier for discharging the same.

8. In a machine for granulating and treating coflee, in combination with cooperating grinding plates, means for feeding material between said plates, an annular chamber having a restricted peripheral discharge opening for receiving and discharging granulated coflee thrown outwardly by said plates, an annular barrier in said chamber between said plates and said discharge opening. means rotatable in said chamber to engage a portion of the material accumulated therein for imparting movement to a portion of said mate.-

" rial diiterent from that otthe remainder thereof so as to cause the cofiee granules to act upon and further reduce the chaff, means to impel the material thus treated over said barrier, and means engaging the material after passage over said barrier for impelling the same through said dis- 7 charge opening.

9. In a machine'for granuiating and treating coii'ee, in combination with cooperating grinding plates, means for feeding material between said plates, an annular chamber having a restricted peripheral discharge opening for receiving and discharging granulated coil'ee thrown outwardly,

by said plates, an annular barrier in said chamber between said plates and said discharge opening, an arm rotatable in said chamber, said arm having a cross section less than that of said chamber whereby it engages only a portion of the material therein for imparting difl'erential move- -ment to said material so as to cause the coffee granules to act upon and further reduce chafl', means associated with said arm for impelling the material thus treated over said barrier and ,means to discharge the material through said discharge opening.

10. In a machine for granulating and treating coffee, in combination with cooperating grinding plates, means for feeding material between said plates, an annular chamber having a restricted peripheral discharge opening for receiving and discharging granulated coffee thrown outwardly by said plates, an annular barrier in said chamber between said plates and said discharge opening, an arm rotatable in said chamber, said arm having a cross section less than that of said chamber whereby it engages only a portion of the material therein for imparting differential movement to said material so as to cause the cofle'e granules to act upon and further reduce chafi, means associated with said arm for impelling'the material thus treated over said barrier, and means to engage and impel through said discharge opening the material which has barrier.

, JOHN C. KOPF.

passed over said 

